Zoe Thomas: Welcome to Tech News Briefing. It's Monday, June 5th. I'm Zoe Thomas for The Wall Street Journal.

All right, onto the episode. Call of Duty is arguably one of the most successful video game franchises ever, and it's at the center of the debate over whether Microsoft should be allowed to buy Call of Duty's owner, Activision Blizzard, for $75 billion. Regulators worry the deal could give Microsoft an unfair edge in the video gaming industry. The UK's Competition and Markets Authority mentioned Call of Duty 41 times in its decision to reject the deal in April. The US Federal Trade Commission cited the game 18 times in its complaint to quash the acquisition. And even though the European Union approved the tie-up last month, that came only after Microsoft pledged to allow competitors to stream Call of Duty and other Activision games over the cloud. Our tech reporter, Sarah Needleman, is with me to discuss what makes this gaming franchise so important. So, Sarah, for people who haven't played Call of Duty, the players are set in a war scenario, but can you tell us how long the game has been around for and just what makes it so popular?

Sarah Needleman: This franchise is two decades old, and what's made it popular is a combination of factors. For one, when it came out, that was just when online multiplayer gaming was starting to come into vogue, so it really came at the right time, and there weren't as many other shooters back then as there are today. And compared to the other shooters that were available back then, Call of Duty really had superior graphics, and it's one of those games that's easy to learn but hard to master. People really gravitated toward it quite quickly. And because it had that early mover advantage, you could say, it continued to snowball over time. And Activision Blizzard invests a large amount of money into the game. The company doesn't say exactly how much, but analysts estimates it's in the hundreds of millions of dollars that they put every year into this franchise.

Zoe Thomas: Okay, so it is very popular, but it's still just one franchise. So why are regulators so fixated on it?

Sarah Needleman: Regulators are concerned that Microsoft could potentially make Call of Duty exclusive to its own cloud gaming platform and locking out others from being able to provide it to players. And so the thinking is that consumers would gravitate towards Microsoft's cloud gaming service. With cloud gaming, it's pretty new, but what the technology does is allow people to play video games from just about any internet connected device with a screen. So essentially smart TVs, mobile phones, laptops. You don't have to plunk down hundreds of dollars on a video game console like the Xbox or PlayStation, nor do you have to spend a lot of money on a gaming PC.

Zoe Thomas: What have Microsoft and Activision said about these concerns?

Sarah Needleman: The company just said that the deal won't hurt competition and that they've committed to licensing Call of Duty games to rivals and to enabling people to stream current and future Activision titles, including Call of Duty, through the cloud gaming platform of their choice.